Internal-combustion engine



July 16, i929.

A. lslGNoRlNl ET AL.

INTERNAL COMBUSTTON ENGINE original Filed May,A 1926 al... n .if .lwilillinn Patented July 16, 1929.

ALBERTO SIGNORINI, 0F NEWV YORK,`

AND GIOVANNI. GELOSO, BROOKLYN, NEW

YORK. i

INTERNAL-COMBUSTION EGINE.

Continuation of application Serial No. 109,319, filed May 15, 1926. This application filed January 1.8, 1928. serial No. 247,760.

' This invention relates to internal combusv lied, an improved arrangement of condone-,

tion chamber togetherwith'mea'ns for admitting an explosive mixture and air into said chamber, whereby the tendency-of an explo-' sive mixture to detonate is effectively checked by creating conditions causing a gradual and complete combustion to take placa.' Another object of the invention is to provide in an engine ofthe character specified,

a novel and improved type ,of combustion chamber, espeo'iallyadapted for -use in connection witl1.engines of the tw'o cycle type,

together with means making it'. possible to 'i eifeotivelyburn a greater quantity of fuelthan Would be-possible in an engine of the ordinary type having a corresponding stroke and bore without detonation, and Without the formation of carbondeposits.`

A further object is to provide in an inter-4 nal combustion engine 'of the two cycle type f a cylinder head of a noveland'i mproved design and means cooperating therewith, ini suri'ng aithorough scavenging .effect inthe cylinder after each explosion.

A still further object i to provide an internal combustion -engine vof the two cycle type o f Van improved design possessing in combination certain features and characteristies insuring i smooth vrunning-'and good operating eiciency of the engine, as well 'as a relatively high Vpower generating capacity.4

Other objects and advantages of the pres'- -ent invention will more fully appear 'as the description Aproceeds and willbe setforth and claimed in the appended claims. u

One ofthe important features of our'pr'esent invention resides'in a combustioncham#` ber of asp'ecial design whereby a regulating action on the fuel 'combustion is automatically obtained vdue to thev mannerl in which the 4explosive charge; and the airassisting combustion arevadmitted to and distributed Within the cylinder; so that by virtue of this arrangement, thenecessity of correcting the vchemical eompositionof 'thefuel used may l2@ reduced- 0 1- totally added,

' wearing surfaces'of tlie cylinder andA piston.

Our invention furthermore possesses eertain additional 'advantages which will be pointedvout in the course of the description.

Referring tothe drawings: i Y Fig. l is a transversalr vertical sectional View of the enginea showing the piston at the end of its compression stroke;

I' Fig. 2 is a similar view showing `the piston atthe 'end of the firing and expansion stroke;

Fig. 3 is a transverse sectional view through" the cylinder head of the engine, taken on the line 34-3 of Fig. 1A; .i

Fig. lzis' a similar view taken on thelineV l-4 of Fig. 1'; and

vided at' one end with a 'relatively small bore 2 and at'iits oppositeend, with a relatively large bore 3. That end `portion of the cylin-v` vderl which is provided with a bore ,2 is surrounded by a cooling jacket 4.' rl`he cylinder is provided with an exhaust port 5 and with inlet ports' eornn'iunicating at theirA inner ends withthe bore 2. .'lhe ports 5 and 6 are preferably located atv diametrically oppo- 1 site sides of the cylinder and are disposed in the same horizontal plane.v The cylinder uso is provided with a port- 7 which communi# eates'at its inner end with the upperend of the bore 3. A valve casing'l 8 is connected with the port Z and houses a spring controlled valve member 9. The casing 8 is provided at its siderwith a nipple 10 which maybe con` nected with' acarburetor (not shown) in a usual manner. The cylinder v1 isyfurtherpro- .vided at its-side Wall with a ductll leading in fromthe larger end of the cylinder and which communicates at its upper end with theport. v

The lower larger end of the cylinder 1 is closed by'a crank casing l2. A shaft 13 is Ajourna'led in thei'casing 12 and a `crank disk 14 isvmounted upon the shaft 13 and housed within thel casing 12. "A v-alve casing l5 is mounted at the side of the crank easing 12 and disposed with its longitudinal dimension f radiallyalined with the apxis of lthe shaft 21.3,

A' spring controlled valve member 16 vis housed in the ,casing and the casing 15 is providedat its side with an inlet opening 17' through which atmospheric air may enter the casing 15 as willbe hereinafter explained.

A pipe 18 is disposed externally of the cyl-r' inde'r 1 and is connected at its lower end with the larger bore 2 of the cylinder and at its upper end with a valve casing 19 which in turn is mounted upon a cylinder head 2O connected with the end of the cylinder 1 and closing the smaller bore 2 thereof. A spark plug 21 is located at the 'centerof theshead 2O and the val-ve casing 19 is provided with .a spring .controlled valve 22v which normally closes the passageway through the casing 19.

The head 2O is provided at its under side with a 'cone-shaped ajutage or nozzle 23 which extends into the smaller bore-2 of the cylinder 1. LThe head 20 is hollow therebyv forming an interior firing chamber 24 and the innervends ofthe casing 19and the spark plug 21 enter the said chamber 24 or communicates therewith. The spark plug 21 is to be connected in a usual manner with a magneto or generator '(not shown).

Apiston 25 1s slidably mounted in the cylinder 1. Said piston is hollow 'and closed at its upper end by a depressed wall forming-a pocket 26. The piston is provided at `its upf per end and at Ythe edge of the pocket with@ the periphery` of the piston andarranged to move in a plane lying between the intake port 6 and' the exhaustport 5. The body of the Assuming that theengine is started with its parts in the positions as shown in F ig. 1 of the drawings. Atmospheric air which has previously been received in the larger bore of the cylinder 1 is compressed by the down wardmovement ofthe piston 25 and this com-- pressed air is forced up through the duct 11 Ainto the jacket 4. At the same time the skirt portion 28 of thepiston 25 moves away from the mixtureport 7 and the mixture is drawn into the upper portions ofthe bore 3 through the casing and the nipple 10 thereof.l W'hen the piston 25 arrives at the lower end of its strolfe the ports 6 and 5 are uncovered.

, The compressed air then passes through the ports Ginto the smaller bore 2 of the cylinder 1. As the skirt portion 28 moves in an upl e ward direction with the piston 25, the mixture whichhas been drawn into the bore 3 is cornpressed in the upper portion of the'said bore and forced through the pipe 18 and the valve Y,

casing 19 into the firing chamber 24 of the head 20, lAt the `same time thepiston 25 moves in an upward direction and the air which has been admitted into the bore 2 of the cylinder 1 is compressed in the upperportion of the bore'2 by ythe walls of the pocket 26 and the ajutage 23 of the head 20. s

l vVihen the piston 25l arrives at the upper end of its stroke theinixt-ure in the firing` chamber A24 is ignited -by the spark plug 21 chamber 24. y

It will be observed thatl duringthe compression stroke of the piston, both the mixture admitted to theiliring chamber 2 4 and the air previously'admitted into the bore 2 of the cylinder are subjected tor pressure simultaneously at botlifends, the individual pressures thus exerted being preferably of` the same value7 due to 'equal displacement of s equivalent surfaces; so that the turbulence' of the mixture is thereby diminished; consequently less tendency is developed in the mixand thus an explosion occurs,in the firing ture to mix with the airwithin bore 2, their y intermmghng bein also lm'pededlin View of the rapidity of theI inovementofthepiston.

Furthermore,it Awill bc'not-edg'thatf the converging walls of the ajutage 23, by .inwardly projecting as they do within the'bore2, virtually form an annular chamber-*at the top of said bore 2 within which compressed air becomes imprisonedby the action'of'the'pistonY making it `physically impossiblefor': said air to intermingle with the mixture withinehamber 24.

By virtue of the arrangement"deseriliedyat the end of the compression strokefas;illus-i trated in F ig. 1, the combustionchamber'bef comes subdividedv into two intercommunicating chambers, one of'which 24 is themliri'n'g.

chamber, and the other one, delimited-bythe outer surface of the ajutage 23 and by the.

upper surface of the piston, we willlc-alluthfe expansion chamber. The expansion-chamber:

is filled with air under pressure, which byfnet being mixed with the combustible particlesof; the fuel mixture Will prevent the possibility y of the process of combustion acquiring` an excessive velocity. `v u Atfirst, when the firing occurs,l and "the:v

expanding gases 'moves rapidly throughjxthe. ajutage 23 and' enter. the plenum of .com-*1 pressed air in the upper end of the boreh2fll (which we have called the expansion 'chain-51;*A

ber),V said air actsas a shock absorbing mixture andv the cylinder and piston walls;v

and subsequently said air gradually suppliesjli't. oxygen to the unburned portions of the fuel xcushion', interposed between the exploding mixtureythus delaying and rendering more 'f gradual and progressive the combustion of the mixture as a whole.

yAs a 'result no excessive maximum presi'- sures are created Within the cylinder but a rel-` atively high average pressure is produced instead, throughout a period of combustion which is longer than it would be under usually normal conditions. j

' By thus prolonging'the period of combustion of themixtu're, other advantages are obi tained due to the fact that no excessive temperatures are created and that the knock is practically eliminated.

Another advantage is that thehigher pressures due to combustion, as against those subsequently developed during expansion, are

still beingexerted whenthe torque of the piston rod has acquired a` fairly high value,

and a smoother running and more uniformdistribution of stresses thereby results.

Still another advantage is the improved combustion due tothe fact that the ni'outh ot the ajutage is surrounded air-on all Sides this giving a chance to the unburnt fractions to mix With an abundant supply of oxygen astheyissue through the mouth of ajutage 2 3.

Still anotherv advantage is thatdue to the isolation of the ri'ng chamber from the pisy ton chamber, thehigher temperatures created during the initial period ot-expansion are confinedl to lparts of the cylinder which are not directly in Contact with thenioving parts; less bindingior ri'ctional resistance due to their expansion are therefore experienced.

Still another bei and piston is the impossibility of the for.- mation of carbon deposits' upon the walls of the cylinder. Due to the improved combuser tion conditions, complete combustion as a rule 'iesults, but under certain conditions, it isv possible that the combustion may not be quite as complete as dui-ing normal operation.

In .this case carbon depositsif any, will be accumulated in the cavity 'which is provided in the center ofthe piston and consequently.no carbon due to incomplete combustion of the fuel can reach the rings of the piston and wear the innervsurface of the cylinder.

Due to the expansion ot' the gases the piston 25 is positively'and quickly moved .upon

its downwardstroke and-the operation above described is repeated. As the piston mov-es in vits upward stroke atmospheric air is drawn into the cylinderat therear of the v'piston and the crank casing through the valve casing land the inlet opening'sl thereof. Wvhen the piston Qis about to reach the low-l er end of its stroke in consequence of an explosion'having previously taken place in the fir-` ingchamber 24, port 5 begins to be une'ov ered, and when said piston actually reaches the end of its stroke both ports 5 and G are uncovered Tby the piston and the compressedv air enters the bore 2 of the cylinder lihroiig'h -itlie'port G and the exhaust or burnt gases pass out ot thebore of the cylinderl result vhich is due to the pe culiararrangement of the combustion chamthrough thel exhaust ports5. 'In that the-lip 27 is interposed-between the ports 6 and 5 the compressed-air is deflected in an upward direction in the bore 2 and ii'i striking the curve-d outer surface of ajutage 23 it is distributed all aroundthe upper part of bore 2 and is then once more deflected downwardly by said curved surface.

. Consequently,the said bore is completely scaveiiged by the inliux of the compressed air and the burnt gases are purged through CII the exhaust ports''leavingl the upper portion 6 is deflected upwardly by lip 2T and then v downwardly b the outer surface of the ajutage 23, sait air exerts a suction around themouth of said ajutage and draws out whatever amount f exhaust gas may still remain in the irin'g chamber, thus insuring thorough scavenging of those parts ot-the combustion,chamber which are not reached by'tlieair direct.

The arrangement described is particularly suitable for use in engines of thetwo cyclel type, but it is obvious that with suitable modilications, the same type of combustion chamber may be used in engines of the tour cycle type; since the regulating action upon' coinv'bustion due to the separation of the conibus tion chamber into a tii'ingchainb'ei: and al separateairor expansion chamber c an be vobtained at the tinieoic the expansion, irrespective of whether the vengine of the. two ,Cycle or of the four cycle type. The ivarious 'details of our 'invention may vary to a certainextent from those shown, i

without departing from the inventive idea,

and the drawings are thcreforeto be underl stood as being' intended for 4illustrative ,purposes only and not in' a liinitin T sense; we accordingly reserve ourselves t-lie rightto carry our invention, into practice in all those ways and `manners which may enter,.'lairly,

'into the scope of the appended claims.

1; The method of operatingK an internal combustion engine o't'the type where a coinbiistible mixture is admitted tothe cylinder, which consists in admitting aiirwithin -th'ecylinder 'from the opposite end, previous tothe compression otl said charge, simultaneously subjecting said gas mixture and air to gradually increasing pressure, while preventing iiiterniinglilng of said air with Isaid charge, then liring said'chai'ge while coiitaining 'a 'quantity-o1 oxygen iiisutlicient for'its complete combustion, thu-s causing said air.

to. gradually increasing pressure from two op-` to absorb the initial force of the explosion, and to delayl the combustion of said mixture.

2. The method of operating an internal combustion engine of the type, where a combustible gas mixture is admitted to the cylinder, which consists in positively isolatingthe explosive mixture lwhile containing a quantity of oxygen insuliicient for its c oinplete combustion, from' a part of the air supplied t'or its` combustion, firing the lcharge while in this isolated condition, and discharging the burning charge into said air in order to complete' its combustion and prolong the period ofcombustion.

The method ot' operating an internal combustion engine of the type where a conib-ustible gas mixture is admitted to the cylinder, which consists in isolating the explosive mixture while containinga quantity of oxygen insufficient for its complete coinbustion, from a part ot' the air supplied for its combustion, admittingsaid air Within the cylinder. from thefopposite end, previous to v,the compression of Said Charge, simultaneously subjecting said gas mixture and air posite ends, while preventing intermiiigling of said air with said charge, tiring the mixture While in this isolated condition, and discharging the burning mixture into said air in order to complete the combustion of said mixture and prolong its period of coinbustion. y y j 4. In an internalconibustion engine of the characterspecitied, the combination, with al cylinder comprising an expansion chamber;-l

of a separate ignition chamber having. a single opening communicating therewith, means for supplying a fuel-air inixture to said ignition chamber, at substantially atmospheric pressure, means lor supplying air also at substantially atmospheric pressure to the expansion chamber, and means for compressing said air and mixture within their respective chainbers, causing said two gaseous bodies -to press against each-other in opposite directions across said opening, previous to the f ignition of said mixture.

5. In an internal combustion engine of the character specified, the combination with a cylinder comprising an expansion chamber,

o1 a separate ignition chamber having a single openin g communicating therewith, means for supplying a. fuel-air mixture at substantially atmospheric pressure tosaid ignition chamber, means for supplying air also'at substantially atmospheric pressure to said expansion chamber, and" means for simultaneously compressing. said mixture and air from two opposite directions, causing. said two gaseous bodies to press-.against each .other in opposite directions across said opening.

6. In an internal combustionjengine of the character speciiied, the combination with ay *cylinder comprising an expansion chamber,

ing a fuel-anl mixture to said ignition 'cliamf'V ber, yot means for inwardly extendingsaid ignition'chamber, causing it to projectl within andto communicate with said expansion chaniber,'and means for supplying and compressing air within said expansion chamber, previous to the ignition of said mixture.

7. In an internal combustion engine of the character specified, the combination with a cylinder comprising an expansion chamber, an ignition chamber, and means for supplying a fuel-air mixture tosaid ignition( chainber,'ofa truste-conical extension Jfor said ignition chamber, causing it to project Within and to communicate with said expansion chamber, forming an annular chamber at the outer vend of saidexpansion chamber, and means cooperating with vsaid fuel-air mixture supplying means, for supplying and compressing air Within said expansion and annular' chambers, previous to the ignition of s'aid mixtui'e.l 1 i 8. In an internal combustionl engine of the charcter specified, vthe combination Iwith a cylinder4 comprising an expansion chamber,

and anignition chamber, of a rusto-conical extension for ysaid ignition chamber, causing it to project within and to communicate with said'expansioii chamber, forming an annular 'chamber at the outer end of said expansion nu'lar chambers, previous to the ignition of .said mixture.

9. In an internal combustion engine of the Vcharacter Speciiied,.the combination with av cylinder comprising an expansion chamber,

an ignition chamber, and means for suplply` ing a fuel-air mixture to said ignition c 4 ber, of means for supplying a scavenging agent to said expansion chamber, and a taperng'nozzleextension for saidignition chamber, causing it to project within and to communicate with said expansion chamber, said extension having an-'inwardlycurved outer Vsurfacesadapted to inwardlydeflect afjet of 4scavenging agent directed against said Surface. p

i l0. In an internal combustion engine of the character specified, the combination with a cylinder comprising an'expan'sion chamber,

an ignition chamber,` and means for supplying a fuel-air mixture to said ignitionchamber, of a nozzle inwardly extending from said ignitioncliamber, causing it to project within and-to communicate withV said expansion chamber, means for supplying and compressing air within said expansion chamber, previous to the ignition of said mixture, and a reciprocating piston within said expansion chamber,-having an inwardly depressed end surface, forming an extension of said expansio'n chamber.

11. In an internal combustion engine of the character specitied,gthe combination with a cylinder comprising an expansionv chamber,

of a larger diameter chamber coaxial therewith, a differential piston reciprocating within said two chambers, means for admitting a fuel-airmixtire to said largerdi'ameter chamber, a closed crankcase at the rearv ofl said piston, means for admitting air to said crankcase, a valve ,controlled connection between said crankcase and said expansion chamber,

exhaust means for said expansion chamber,

an ignition chamber, a valve controlled connection between said larger diameter chamber and said ignition chamber, and an extension for said ignition chamber, causing it to project within and to communicate with'said expansion chamber, forming an annular chamber at the outer end of said expansion chamber, preventing the air in the expansion chamber from mixing with the fuel mixture in the ignition chamber at the end of the compression stroke.

, l 12. In an internal combustion engine of the character specified, the combination with a cylinder comprising an expansion chamber,

of a larger diameter chamber coaxial therewith, a differential piston reciprocating within said two chambers, means for ladmitting a a fuel-air mixture to said larger diameter chamber, a closed cranlrcase at the rear of said piston, meaiis for-admitting air to said crankca'se, a valve controlled connection be- .tween said crankcaseand said expansion chamber, exhaust means for said expansion chamber, an ignition chamber, a valve controlled'connection between said larger diameter and said ignition chamber, means associated with said piston for directing 'air ad-A mitted to said expansion chamber towardsthe outer end thereof, and a frusto-conical extension for said ignition chamber, causing it to project within and to communicate with said expansion chamber, forming an annular chamber at the outer end thereof, said exten- Y.

sion having an inwardly curved outer surface adapted to inwardly deflect said-air.

13. In an internal combustion engine of the character specified, the combination with a cylinder comprising an expansion chamber, of a larger diameter chamber coaxial therewith, a differential piston reciprocating within said two chambers, means for admitting a fuel-air mixture to said larger diameter chamber, a closed crankcase at the rear of said` piston, means for admitting air to said crankcase, a valve controlled connection between said crankcase and said expansion chamber, exhaust means for said expansion chamber, an ignition chamber, a valve controlled connection between said larger diameter and said ignition chamber, means associated with said piston for directing airadmitted to said expansion chamber towards the outer end thereof, a frusto-conical extension for said ignition chamber, causing it to project within and to communicate with said expansion chamber, forming an annular chamber at the outer end thereof, said extension having an inwardly curved 4outer. surface` hea-d, said'cylinder having at an intermedil ate point a port for admitting a scavenging agent into the cylinder, apiston mounted for reciprocatory l*movement in the cylinder, forming a compound air chamber at the outits compression stroke, said piston being holer endof the bore in the cylinder at the end of low and having one end permanently closed lby a wall provided with a cavity forming an extension of said compressed air chamber, and the side walls of the ajutage being 'inclined to form a tapering nozzle extending within said chamber.- y

- ALBERT@ SGNRINL GIOVANNl GELSU. 

